When you have a standing prescription every month...?!
Question: Why would the doctor who prescribes you that medication send you to take a drug screen for it?
Answers: Why would the doctor who prescribes you that medication send you to take a drug screen for it?
I assume this is for a narcotic.....To make sure you are taking it. The drug screens will detect that drug and the amount of it - it makes sure the patient is taking it and taking it as directed (and not selling it).
If not a narcotic - it would be to make sure that the amount of medication in your system is at theraputic levels and not either too high (toxic) or too low (inefficient).